Because the atrial rate is so fast, and the action potentials produced are of such low amplitude, P waves will not be seen on the ECG in patients with atrial fibrillation. At times, the P wave ...

The waves on an ECG include the P wave, Q wave, R wave, S wave, T wave and U wave. Interval: The time between two specific ECG events. The intervals commonly measured on an ECG include the PR ...